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Cold Start And Koer Help

  • Thread starter Thread starter Keith5.0GT
  • Start date Start date May 31, 2017
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Keith5.0GT

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May 29, 2017
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Jun 13, 2017
#21
  • Jun 13, 2017
  • #21
i set it at 20k and 200k. thats all i know. but I'm gonna take a break from it because the car needs an alternator now. and I'm going to do the lower intake gasket, again. thank you for the answers
 

Keith5.0GT

Active Member
May 29, 2017
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Jun 15, 2017
#22
  • Jun 15, 2017
  • #22
Alright i learned a lesson. my volt meter battery was shot, giving me false readings. so I'm re-testing everything. i think i need an alternator too. but i still have koer codes 41,91,33 so I'm going to do research through your forums.
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
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Jun 15, 2017
#23
  • Jun 15, 2017
  • #23
Keith5.0GT said:
Alright i learned a lesson. my volt meter battery was shot, giving me false readings. so I'm re-testing everything. i think i need an alternator too. but i still have koer codes 41,91,33 so I'm going to do research through your forums.
Click to expand...
my vom knows how stupid I am, it will flash 'low battery dumbass' on the screen!
 
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Keith5.0GT

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Jun 18, 2017
#24
  • Jun 18, 2017
  • #24
well I'm in the process of doing my lower intake gaskets for a second time. so getting that right and replacing any vacuum lines that look bad I'm hoping to fix the cold start trouble. ill let ya know. thanks
 

jrichker

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#25
  • Jun 19, 2017
  • #25
Some tips and tricks to help you on your way...

All other types of intake manifolds
Vacuum line connections:
One large vacuum line from the upper front goes to the carbon canister

One large vacuum line from the rear goes to the vacuum tree.

One small line in the front feeds the Smog pump solenoid control valves on the rear of the passenger side wheel well..

One small line in the rear goes to the fuel pressure regulator.

One small line in the rear goes to the EGR suction regulator.

One large line in the rear goes to the PVC valve.

Diagram courtesy of Tmoss & Stang&2birds - Typical Vacuum Routing for a Fox stang 5.0:

Diagram courtesy of Tmoss & Stang&2birds - Intake manifold bolt tightening sequence for a 5.0 Fox stang:


Intake manifold to head bolts
--Step 1 96 in/lbs
--Step 2 16ft/lbs
--Step 3 23-25 ft/lbs

See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host) for help on 88-95 wiring http://www.veryuseful.com/mustang/tech/engine/

Here's some tips...

Tools: a good torque wrench is a must have item. A razor blade scraper that holds a single edge razor blade from Home Depot or Ace hardware is another handy thing. Get a Chilton or Haynes shop manual - you'll need it for the bolt torques and patterns. The intake manifold has an especially odd pattern. You'll need access to a timing light to set the timing after you re-stab the distributor. Look in the A/C repair section for the fuel line tools. They look like little plastic top hats. You will need the 1/2" & 5/8" ones. The hat shaped section goes on facing the large part of the coupling. Then you press hard on the brim until it forces the sleeve into the coupling and releases the spring. You may need someone to pull on the line while you press on the coupling. Put some motor oil on them when you put the line back together.

The A/C Compressor comes off with lines still connected. Mark all the electrical, smog and vacuum lines with tags to help you remember where to re-connect them. If you have a digital camera, take several pictures.

Whatever you do, don't skimp on cleaning the gasket surfaces. New gaskets need to seat against bare metal and not the residue left from the old gaskets in order to seal leak free. This is the most time consuming and tiresome part of the job. Put some cardboard in the lifter valley to help catch the gasket scrapings. Have a shop vacuum handy to suck up the scrapings and any coolant that leaked into the lifter valley.
Look for little things that need to be replaced like the short hose from the thermostat hosing to the water pump, damaged vacuum lines and hose clamps that are rusted or broken.

Plan on cutting the thermostat to water pump hose, or removing the thermostat housing. Also plan on removing the distributor to get clearance to remove the intake manifold. Remove #1 spark plug, stick your finger in the spark plug hole and crank. When your finger gets air moving past it, stop cranking. Turn the engine until the timing marks line up with the pointer. Now you can pull the distributor out. Be sure to put a rag or cap in the block where you removed the distributor. It will save you trouble if something falls into the empty distributor hole.


My favorite trick that saves time and effort is the stay in place gasket. Be sure that you scrape (don't use a wire brush) all the old gasket material off, then clean all the surfaces with acetone or MEK.

When the surfaces are clean, use weather strip adhesive on the head to manifold surface. Also use the weather strip adhesive on the side of the gasket that mates to the head. When you are done, the head surface and the gasket surface that mate together will have weather strip adhesive on them. Follow the instructions on the tube or can and when it gets tacky, press the gasket down on the head.

Clean the area where the rubber rails mount to the block in front and in the rear with more acetone or MEK and do the same trick with the weather strip adhesive that you did to the heads.

Coat the rubber seals and the gasket area around the water passages with lots of Blue Silicone gasket sealer and put it together. TADA! no leaks, and no gaskets that shifted out of place.

Fuel injector seal kits with 2 O rings and a pintle cap (Borg-Warner P/N 274081) are available at Pep Boys auto parts. Cost is about $3-$4 per kit. The following are listed at the Borg-Warner site ( http://www.borg-warner.com ) as being resellers of Borg-Warner parts:

http://www.partsplus.com/ or http://www.autovalue.com/ or http://www.pepboys.com/ or http://www.federatedautoparts.com/

Most of the links above have store locators for find a store in your area.

Use motor oil on the O rings when you re-assemble them & everything will slide into place. The gasoline will wash away any excess oil that gets in the wrong places and it will burn up in the combustion chamber. Heat the pintle caps in boiling water to soften them to make them easier to install.

Plan on doing an oil change within 2 hours of run time on the engine. This will get the debris and coolant out of the oil pan.

Consumable items:
Upper manifold gasket
Fel Pro 1250 or equal lower manifold gasket set.
Short formed hose between thermostat hosing and intake manifold
6 ft 7/64" or 1/8" vacuum hose
2 ft 1/2" heater hose
1 1/2 ft 5/8" heater hose
Blue Silicone sealer
ARP antiseize or equal for the bolts
4 each 3/4" hose clamps (spare item in case the old ones are bad)
4 each 1/2" hose clamps (spare item)

What can happen if you don’t use the stay in place gasket…

Ask Nicoleb3x3 about the intake gasket that slipped out of place and caused idle and vacuum leak problems that could not be seen or found by external examination. Spay everything with anything you have, and you won't find the leak...
 
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Keith5.0GT

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May 29, 2017
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Jun 19, 2017
#26
  • Jun 19, 2017
  • #26
Thanks a lot for the info. I've got it apart and have gaskets ordered. What I found, my first time doing this I didn't put a thick enough bead of permatex in the valley on the front and back so I didn't have a good seal. Had a few gaps. I'm hoping that when I do it right, my cold start problems will be fixed. Also some oil in the upper intake where the charcoal canister vacuum line connects. Pcv rattles like it should so maybe my unsealed lower intake has caused that blow by too. I'm going to replace any questionable vacuum lines too. I'll let you all know how it goes. Thanks again.
 

Keith5.0GT

Active Member
May 29, 2017
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Jun 25, 2017
#27
  • Jun 25, 2017
  • #27
well, I've finally redone the lower intake gaskets and replaced any questionable vacuum lines. bad news is, still have a crappy cold start, popping and bucking if i drive away cold, and koer codes 41,91,33. the good news is, the car runs a lot smoother now, after it warms up a few minutes. so I've put so many hours and dollars into this car over the past 5 months of ownership, and its been a lot of learning and let downs. but i got over the discouragement and ordered some o2 sensors. why?
because I've cleaned 10 pin connectors, checked maf volts, checked act volts, new egr, new egr sensor, new gaskets everywhere, new ect, new iac, tps set, idle set, fuel pressure 39 psi, and i just don't know what else to do. only things that aren't new are maf, act, and o2 sensors. theres only so many things left. it has to be one of them! tired of this battle but I'm gonna keep going.
 

Keith5.0GT

Active Member
May 29, 2017
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Jun 27, 2017
#28
  • Jun 27, 2017
  • #28
i tried bumping fuel pressure from 39 to 42 psi and cold start was better and it didn't pop when i drove away. so maybe on the right track.do you know how high i can safely go? my mods are cold air intake, 70 ish mm throttle body, trick flow upper and lower, pulleys, headers and 3" exhaust with no cats.
 
Last edited: Jun 27, 2017

jrichker

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Jun 27, 2017
#29
  • Jun 27, 2017
  • #29
Fix the 41/91 codes and set the fuel pressure back to 39 PSI. If you are going to do it, do it right and fix the sensor problem. Playing with the fuel pressure is a Band-Aid to cover over some unresolved problems.

I gave you the code 41/91 test path on the first page of your post. Go back and actually do it.
 
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Keith5.0GT

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May 29, 2017
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Jun 28, 2017
#30
  • Jun 28, 2017
  • #30
well i did do it, and I've gone through a lot of your info and I'm thankful its here. when i got to the part about testing the o2's, i just replaced them instead. i also turned fuel psi back down like you said. cold start was a lot better but eventually it tried to stall a few times. still have codes 41,91,33 and running lean i think. so i will go through your data and see if there is anything i have missed.
 

Keith5.0GT

Active Member
May 29, 2017
83
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28
Oct 28, 2017
#31
  • Oct 28, 2017
  • #31
jrichker said:
Fix the 41/91 codes and set the fuel pressure back to 39 PSI. If you are going to do it, do it right and fix the sensor problem. Playing with the fuel pressure is a Band-Aid to cover over some unresolved problems.

I gave you the code 41/91 test path on the first page of your post. Go back and actually do it.
Click to expand...


alright i think i just solved the mystery!!!! i did as much of the surging idle checklist as i could, i bought new parts when i didn't need to, and finally.......i couldn't stop thinking about how it will have a poor cold start but its better if i up the fuel pressure. but on a warm start it didn't matter.....so with everything else done, even though the maf sensor was getting volts, i bought another. and i can't believe the difference. stock fuel pressure and it cranked up, no stalling. idles a lot smoother (had to reset base idle) and even smells different. i can't believe it. I've been trying for 6 months to figure this out. wow. just thought id let anyone know that reads this. thank you everyone.
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
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213
polk county florida
Oct 28, 2017
#32
  • Oct 28, 2017
  • #32
Thanks for the update, most times when a problem gets resolved we never know about.
Have a beverage on me.
 
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Keith5.0GT

Active Member
May 29, 2017
83
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Oct 28, 2017
#33
  • Oct 28, 2017
  • #33
karthief said:
Thanks for the update, most times when a problem gets resolved we never know about.
Have a beverage on me.
Click to expand...
Yeah it helps if people say what it actually was. Thanks for the beverage haha
 
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Keith5.0GT

Active Member
May 29, 2017
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Nov 3, 2017
#34
  • Nov 3, 2017
  • #34
karthief said:
Thanks for the update, most times when a problem gets resolved we never know about.
Have a beverage on me.
Click to expand...
Also wanted to add, it got rid of my codes 41 and 91. Wooohooo
 
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